Power Optimization in Fault-Tolerant Mobile Ad Hoc Networks

In this paper, we investigate the transmission-power assignment problem for k-connected mobile ad hoc networks (MANETs), the problem of optimizing the lifetime of a MANET at a given degree k of connectivity by minimizing power consumption. Our proposed solution is fully distributed and uses a model-based transmission power adaptation strategy based on model-predictive control. Specifically, a stochastic model of the network is used by a state estimator to predict the network´s future degree of connectivity and remaining energy. The predicted states are used by an optimizer to derive an optimal transmission power assignment sequence which tracks the desired connectivity level k while minimizing energy consumption. Our experimental results on a simulated wireless sensor network comprising 100 mobile nodes reveals that our localized topology control algorithm provides an almost identical control policy to that of a globalized scheme which is solving a fully observable problem. The difference, of course, is in the scalability of our localized solution, which requires much less communication bandwidth and energy than the globalized approach.